The present invention relates to a hydraulic motor. More particularly, the invention relates to a hydraulic motor which includes a stationary housing, a rotor disposed in the housing and provided with a plurality of axially extending and outwardly open hollow pistons and a plurality of cylinders, each cylinder being movable over the respective piston and having a couple of axially disposed journals cooperating with cam tracks formed on the inner wall of the stationary housing. The hydraulic motor of the foregoing type further includes a control shaft mounted within the rotor and adapted to transmit pressure fluid from the pressure fluid lines to the hollow radial pistons.
Hydraulic motors of the type under discussion are known in the art. One of such motors is disclosed, for example in British Pat. No. 12 42381. These hydraulic motors have the advantage, that due to the above described design with radial pistons, they can be designed to be compact in the radial direction, in other words with a relatively small outer diameter of the housing. The utilization of such hydraulic motors, does not depend solely on the outer diameters of the motors. If a hub wheel hydraulic motor is used as an individual drive of the vehicle wheel, efforts should be made to obtain the shortest possible overall length of such a motor.